Atlético Madrid is into the UEFA Champions League quarterfinals, staving off an early hint at drama from visiting AC Milan to post a 4-1 victory. The result gives Diego Simeone’s team a 5-1 aggregate win over the seven-time champions, with goals from Diego Costa (two), Arda Turan, and Raúl Garcia delivering the win at the Vicente Calderón.

Costa’s first goal came in spectacular fashion in the third minute when, at full stretch, the Spanish international redirected Koke’s cross home at Christian Abbiati’s far post. The lead proved short-lived as Kaká headed home from close range after a Andrea Poli cross to make it 1-1.

Before halftime, however, Turan’s deflected volley beat a helpless Abbiati to restore Atlético’s two-goal edge, with a header from Garcia mid-way through the second period eliminating all of Milan’s lingering hopes. Demoralized, Milan saw Costa score his seventh goal of the competition in the 85th minute, completing its disappoint night in Madrid.

The victory sends the Colchoneros into the final eight for the first time in 17 years, while Milan exit the competition at the first knockout round for the second consecutive tournament. Ensuring no Italian team will be in the final eight, Milan’s early exist adds to frustrations incurred by a 11th place standing in Serie A.

The Rossoneri entered the day with a 1-0 deficit after Costa’s 83rd minute winner three weeks ago in Milan gave Atleti a 1-0 lead. Costa doubled that lead three minutes into the second leg when Koke, cutting in from the right, vaulted a ball toward Abbiati’s far post. Reaching with his left leg shoulder-high from five yards out, the Atlético striker put his teammate’s pass into the back of the Milan goal before landing flat on his tailbone. Up two, Atlético appeared destined for an easy night.

That appearance evaporated just before the 30 minute-mark when a ball put toward the byline on the right allowed Poli to put an uncontested ball toward Thibault Courtois’ far post. The gigantic Belgian was unable to traverse the goalmouth in time to stop Kaká’s easy header, with right back Juanfran having lost track of an attacker who’s up to 30 Champions League goals.

Milan’s control of possession through the game’s next 10 minutes went for naught when a long ball chested down for Turan gave the Turkish international a chance from the top of the arc. Volleying a ball after a quick thigh trap, the Atlético midfielder put his shot off Daniele Bonera and past Abbiati, with the deflection preventing the Milan keeper from denying the hosts a 2-1 halftime lead.

When Milan couldn’t pull the goal back early in the second, the match adopted a feeling of inevitability – as if Atlético had already qualified for the quarterfinals. When Garcia headed his team’s fourth goal home in the 70th minute, all doubt left the Calderón. A goal starved AC Milan would need three to move past their favored hosts, a hope rendered mute when Costa blasted his seventh goal of the competition in from the right edge of the six-yard box.

That favorite’s status, in doubt as Atlético struggled ahead of the first leg, proved well-earned at the end of 180 minutes, with a Milan team that’s limped through its Serie A campaign proving no more capable in Europe. Atlético, conversely, has reclaimed the form that carried them through January – quality that made them dark horses in this competition.

Though potential quarterfinal opponents will prefer the Atleti to Bayern Munich or Real Madrid, Atlético will be dangerous come the quarterfinals.